ENGLISH
REFERENCE

idle

adj. · v. · n.
US //ˈaɪdəɫ// UK //ˈaɪdəl// idle
  1. 1 not in use (adj.)
    B2 Upper Intermediate

    not being used or not working at the moment.

    not in active use or operation; describing resources or machinery that are currently functional but unoccupied.

    Example

    The machines in the factory stood idle during the long holiday weekend.

    Example

    The company struggled with the high costs of maintaining idle equipment while waiting for the new contracts to be signed.
  2. 2 lazy (adj.)
    B2 Upper Intermediate

    lazy or not willing to work.

    habitually avoiding work or exertion; lazy or slothful in character.

    Example

    He was an idle student who preferred playing games to doing his homework.

    Example

    The manager warned that idle employees would not be considered for the year-end performance bonuses.
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  1. 3 useless or silly (adj.)
    C1 Advanced Formal

    having no real purpose or value; silly.

    lacking substance, utility, or a serious basis; often used to describe talk, threats, or curiosity.

    Example

    She didn't want to waste time on idle gossip about her neighbours.

    Example

    The diplomat dismissed the rumours as idle speculation, insisting that no formal agreement had been reached.
  2. 4 engine running slowly (v.)
    B2 Upper Intermediate

    when an engine runs slowly while the vehicle or machine is not moving.

    to run at a low speed or out of gear; describing an internal combustion engine ticking over without performing work.

    Example

    The taxi driver let the car idle while he waited for the passenger to come outside.

    Example

    Modern vehicles are often designed to shut off automatically rather than idle at traffic lights to improve fuel efficiency.
    • tick over
  3. 5 to waste time (v.)
    C1 Advanced Literary

    to spend time doing nothing or being lazy.

    to spend time in an inactive or lazy manner; often used with 'away' when transitive.

    Example

    They idled away the afternoon sitting by the river and talking.

    Example

    He spent his inheritance idling away his youth in expensive resorts instead of pursuing a career.
  4. 6 engine state (n.)
    C1 Advanced Technical Technical

    the state of an engine when it is running but not moving.

    the lowest power setting or speed at which an engine can run steadily.

    Example

    The mechanic adjusted the idle because the car kept stalling at red lights.

    Example

    The pilot reduced the engines to idle as the aircraft began its final descent toward the runway.
    • low power
Etymology 1

From Middle English idel, ydel, from Old English īdel, from Proto-West Germanic īdal, from Proto-Germanic īdalaz. Cognate with Dutch ijdel (“vain, meaningless”), ijl (“rareified, skinny”), iel (“thin, slender”); German Low German iedel (“vain, idle”); German eitel (“vain, conceited”); and possibly Old Norse illr ("bad"; > English ill).

Etymology 2

From Middle English idelen, from Old English īdlian, from Proto-West Germanic *īdalēn. Cognate with German eiteln (“to make empty, free up”).

Etymology 3

From Middle English idel, ydel, from Old English īdel (“idleness”), from the adjective (see above).

Word family
  • Adjectiveidle
  • Adverbidly

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